JPH0524915U - Exhaust system for automobile - Google Patents

Abstract

(57) [Summary] [Purpose] An exhaust system equipped with a catalytic converter can be diverted to another exhaust system which does not have a catalytic converter while maintaining its basic form. [Structure] One end of a catalytic converter case 2 is connected to an exhaust manifold 4, the other end of the case 2 is connected to a muffler via an exhaust pipe 5, and a connecting surface between the case 2 and the exhaust manifold 4 is connected. One or a plurality of holes 20a are interposed by the partition plate 20 to prevent the case 2 from functioning as an expansion chamber of the muffler and reducing the sound deadening effect.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a vehicle exhaust system.

[0002]

[Prior Art]

 In recent years, exhaust systems equipped with catalytic converters have been widely used as measures against exhaust gas from automobiles. FIG. 5 shows such an exhaust device. In the catalytic converter indicated by 1 in the figure, one end of the catalytic converter is connected to the exhaust manifold 4, and the other end is connected to the muffler 6 via the exhaust pipe 5. It is connected to the. The catalytic converter 1 is made up of a catalyst 2 housed in a case 2. The catalyst 3 in the catalytic converter 1 prevents hydrocarbons, carbon monoxide, nitrogen oxides, etc. contained in the exhaust gas. It is being purified.

By the way, as measures against exhaust gas, in addition to the system using the catalytic converter 1, so-called engine modification or recirculation of a part of exhaust gas to the engine intake system is also known, in which the characteristics of the engine itself are improved. There is a method using an exhaust gas recirculation system (EGR), etc., which is used in the exhaust system of automobiles from each viewpoint. On the other hand, in the manufacture of automobiles, parts or devices are being standardized from the viewpoints of consolidating production equipment, product management, cost reduction, etc. Is becoming

[0004]

[Problems to be solved by the device]

 However, in the exhaust system equipped with the catalytic converter 1, the catalyst 3 and especially the monolith catalyst have a sound deadening effect, so that it is sufficient to use a small muffler 6. Therefore, if the exhaust device equipped with the catalytic converter 1 is to be diverted to another exhaust system that does not require the catalytic converter, the catalyst 3 is naturally taken out from the case 2, and the muffling effect is obtained. In this case, it is necessary to change the muffler 6 to a larger one, or install another muffler on the exhaust pipe 5 in order to mitigate this noise, and divert it while maintaining its basic form. Becomes impossible.

The present invention has been made in view of the above background, and an exhaust system for an automobile that can obtain a desired muffling effect even if the basic form equipped with a catalytic converter is maintained and it is diverted to another exhaust system. The purpose is to provide.

[0006]

[Means for Solving the Problems]

 To achieve the above object, the present invention connects one end of a catalyst converter case to an exhaust manifold, connects the other end of the case to a muffler through an exhaust pipe, and connects the case and the exhaust manifold. It is characterized in that a partition plate having one or a plurality of holes is interposed on the coupling surface with.

Further, the present invention may be arranged such that a honeycomb structure without a catalyst or a sound absorbing material is housed in the case instead of interposing the partition plate.

[0008]

[Action]

 In the automobile exhaust system configured as described above, when a partition plate having a hole in the coupling surface between the case and the exhaust manifold is interposed, the inside of the case functions as an expansion chamber for the muffler to produce a sound deadening effect. .. In addition, when the honeycomb structure that does not support the catalyst is stored in the case, the honeycomb structure itself exists as a sound deadening function member, and when the sound absorbing material is stored in the case, the sound absorbing material absorbs sound. It will be effective.

[0009]

【Example】

 Embodiments of the present invention will be described below with reference to the accompanying drawings.

1 and 2 show a first embodiment of the present invention. Since the overall structure (basic shape) is the same as that shown in FIG. 5 described above, only the main parts are shown here and the same parts as those shown in FIG. To do. In the first embodiment, the catalytic converter case 2 is composed of a large-diameter main body portion 11 and a small-diameter outlet portion 12 connected to the main body portion 11, and the main body portion 11 and the outlet portion 12 are provided. Flanges 11a and 12a are respectively provided at the open ends of the. The case 2 is integrally coupled to the exhaust manifold 4 by a bolt 13 and a nut 14 so that the flange 11a of the main body 11 is aligned with the flange 4a of the exhaust manifold 4. At the joint between the case 2 and the exhaust manifold 4, a porous partition plate 15 having a large number of small holes 15a is interposed between a pair of gaskets 16 in a sandwich shape. On the other hand, an annular sound absorbing material 17 is housed inside the case 2 instead of the catalyst 3 (see FIG. 5), and is fitted and held on the inner peripheral surface of the case 2. The sound absorbing material 17 is made of a material capable of absorbing high-frequency (2 KHz or more) sound and is formed by sintering. The exhaust pipe 5 is connected to the outlet portion 12 of the case 2 by utilizing the flange 12a thereof. Further, a bolt insertion hole 15b through which the bolt 13 is inserted is provided on the outer periphery of the multi-hole partition plate 15.

In the exhaust system for an automobile configured as described above, exhaust gas from the exhaust manifold 4 passes through the small holes 15a of the porous partition plate 15 and flows into the case to be rapidly expanded. The inside of Case 2 just functions as an expansion chamber for the muffler, producing a sound deadening effect. At the same time, the sound absorbing material 17 in the case 2 absorbs the sound, and the sound is silenced just below the manifold near the source of the mechanical sound, so that the sound is more effectively silenced. As a result, even if the exhaust device equipped with the catalytic converter 1 (FIG. 5) is used for another exhaust system that does not require a catalytic converter while maintaining its basic shape without making any changes to the muffler 6. As a result, the muffling effect will not decrease, and the exhaust system can be shared.

3 and 4 show a second embodiment of the present invention. The feature of the second embodiment is that, instead of the porous partition plate 15, a partition plate 20 having a plurality of relatively large holes (20 in this case) 20 and 20b is provided to the case 2 and the exhaust manifold 4. The point is that it is inserted in the joint with. The holes 20a and 20b of the partition plate 20 are formed by burring here, and the respective hole diameters d ₁ and d ₂ are set so that the total opening area thereof is smaller than the flow passage cross-sectional area of the exhaust manifold 4. Has been done. With such a configuration, the inside of the case 2 functions as an expansion chamber for the muffler, and the sound deadening effect is produced as in the first embodiment. Note that the partition plate 20 may have only one hole.

In the above two embodiments, the partition plates 15 and 20 and the sound absorbing material 17 are both held, but the present invention provides either one of the partition plates 15 and 20 and the sound absorbing material 17. It is also a good configuration. Further, the present invention may omit the use of the partition plates 15 and 20 and the sound absorbing material 17 in the above two embodiments, and may house the catalyst-free honey-comb structure in the case 2. Provides a desired silencing effect due to the silencing function of the honeycomb structure itself. Further, in the second embodiment, the partition plate 20 is provided with the two holes 20a and 20b, but the number of the holes may be one, or three or more.

[0014]

[Effect of the device]

 As described above in detail, according to the exhaust system for an automobile according to the present invention, the case of the catalyst converter is made to function as a silencer, so that the basic form equipped with the catalyst converter is maintained. It became possible to use it for other exhaust systems, and it had the effect of greatly contributing to the improvement of automobile productivity and the reduction of production cost. In addition, since the silencer is placed near the sound source, it has the effect of realizing an exhaust system that is extremely effective in eliminating noise.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an essential part showing a first embodiment of an exhaust system for an automobile according to the present invention.

FIG. 2 is a plan view of a porous partition plate used in the first embodiment.

FIG. 3 is a cross-sectional view of essential parts showing a second embodiment of the exhaust system.

FIG. 4 is a plan view of a partition plate used in the second embodiment.

FIG. 5 is a cross-sectional view showing the overall structure of an exhaust device equipped with a catalytic converter.

[Explanation of symbols]

 2 Case for catalytic converter 4 Exhaust manifold 5 Exhaust pipe 6 Muffler 15 Porous partition plate 15a Small hole 17 Sound absorbing material 20 Partition plate 20a hole

Claims (3)

[Scope of utility model registration request] 1. A catalyst converter case is connected to an exhaust manifold at one end thereof, and the other end of the case is connected to a muffler through an exhaust pipe, and one or more is provided on a connecting surface between the case and the exhaust manifold. An exhaust system for an automobile, characterized in that a partition plate having a plurality of holes is interposed. 2. A catalyst converter case is connected to an exhaust manifold at one end thereof, and the other end of the case is connected to a muffler through an exhaust pipe, and a catalyst-free honeycomb structure is housed in the case. An exhaust system for an automobile, which is characterized in that 3. The exhaust system for an automobile according to claim 2, wherein a sound absorbing material is housed in a case instead of the honeycomb structure.